The present disclosure relates to a method for producing a high burst slider zipper which allows for bottom filling of reclosable packages, such as large bags, and further provides increased resistance to damage from the dropping or shock loading of the filled package. This is achieved by providing a peel seal or other frangible or separable connection between the zipper profiles, and by sealing a portion of one of the flanges to itself by a hard seal above the peel seal. This causes the external forces on a bag from bottom filling or shock loading to be directed toward the hard seal and further directed so as to cause a shear force against the peel seal, thereby increasing the resistance of the package to external forces.